From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <39AAA991.32FDF058@mvista.com> Date: Mon, 28 Aug 2000 11:04:01 -0700 From: Cal Erickson Reply-To: cal_erickson@mvista.com MIME-Version: 1.0 To: Seong-kyu Ko CC: linuxppc-embedded@lists.linuxppc.org Subject: Re: Problems of the corss-compiler. References: Content-Type: text/plain; charset=us-ascii Sender: owner-linuxppc-embedded@lists.linuxppc.org List-Id: Seong-kyu, In the MSR of the PPC processor there is a bit that indicates whether there is hardware floating point unit available. This bit should be set in the state to turn hardware floating point off when not present. In my experience even on PowerPC cpus which have hardware floating point some people do not need or want to use it. So they make sure that the MSR is set properly. That being said, it is important to either make sure that bit is always set properly or provide the proper library routines to make sure that you are getting the desired results. For instance, the 8xx family of PPC does not have floating point hardware. So you provide libraries that do software floating point. The one area where this comes into play is when using va_args in the runtime of the C-library. It is typical to save the registers and the floating point state upon entry. If the routine does not check the MSR bit and branch around the floating point state save code then the system will crash as a result of the floating point instructions. So the fix is to eliminate that code from the library and not depend on the state of the MSR bit. This makes it necessary to have a special library for the 8xx family of PPC processors. Cal Seong-kyu Ko wrote: > Hi everyone. > First, I'm sorry for my weak English. > > Well, Now I build a powerpc cross-compiler. > so I compiled some binary using that cross-compiler, but > I have some problems. > > I think cross-compiler is not problem. > because I compile kernel with that cross-compiler, and > kernel runs good. > > but, init, shell etc thease binaries have some problems. > shell cant recieve argument, and some binaries print 'segmentation fault' > > I don't know why my compiler can't compile well. > > These are the packages that I used. > 1. binutils-2.10 > 2. gcc-2.95.2 > 3. glibc-2.1.3 (add-ons : glibc-crypt-2.1, glibc-linuxthreads-2.1.3) > > First, I compile the binutils for powerpc cpu. > Second, I build cross compiler with gcc. > Third, I compile glibc for powerpc with cross compiler that I made. > Last, I re-build cross compiler include glibc for library. > > Please tell me what do you think about that And why the problem happen. > I'll wait your answers. > thank you. > -- =========================================================================== Cal Erickson MontaVista Software Inc. Customer Support Engineer 490 Potrero Avenue Phone (408) 328-0304 Sunnyvale CA 94085 Fax (408) 328-9204 e-mail cal_erickson@mvista.com Pager 877-566-2012 support 1-800-759-8888 pin 202-7489 web http://www.mvista.com support e-mail: support@mvista.com eCode: http://cal@work.com.ecode.com =========================================================================== ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/